Comment 4 for bug 1587010

per Brian's question:
What *seems* to be happening is that our mysql password for the trove user is getting changed as we perform this controller delete operation.

We have a "mysql password" we're auto-generating and storing in our plugin attributes/metadata.
Here's a bit of environment_config.yaml:
attributes:
  metadata:
    ..
    mysql_password:
      generator: 'password'

When the original 3 controllers have completed provisioning, a particular value will exist for the password, and this appear the same on all 3 controllers. for example:
root@node-9:~# hiera fuel-plugin-tesora-dbaas
{"tesora_accept_terms"=>"I AGREE",
 "tesora_guest_download_username"=>"xxxxxxxx",
 "tesora_guest_download_password"=>"xxxxxxxx",
 "metadata"=>
  {"mysql_password"=>"bnL1TIMlk9lQbG4ZTClyF1YN",

When the primary controller has been deleted and the environment redeployed, the value for 'mysql_password' will have changed.
(We see a problem because the plugin's mysql code has run, but it appears the trove config files have not been regenerated.)

Is there a way to prevent this regeneration of the password?

Does this password regeneration happen on all changes to controllers, or just ones affecting primary_controller?
Does it happen on any other events/conditions?